Teammates: Instructor: add instructor: 'display to students as' textbox should be enabled only if the checkbox is checked

[taniach]

If the checkbox is not checked, the textbox should be disabled. Currently, it is always enabled.

The default value after adding a new instructor is 'Instructor' if the checkbox is checked and the textbox is empty. Suggestion: Load the page with the checkbox unchecked and a disabled textbox containing the value 'Instructor'. The examples (e.g co-lecturer, teaching assistant) can be given in the tooltip.

[damithc]

The more common case is to display to user. Hidden instructors are rare. So default should cater for the common case.

[taniach]

Then we can have a textbox with the value 'Instructor' inside since it is the default. Blank textbox changing to 'Instructor' on submit seems misleading.

[HirdayGupta]

Hi @amarlearning! Didn't know you were working on this! 😅

I had some code ready to go that takes a different approach to this issue (taking into consideration the follow up comments made by @damithc and @taniach). Submitting the PR to see what devs have to say! 😃